Feed collet or pusher



Nov. 10, 1925-. 1,561,040

E. H. WHEEL-ER v -FEED COLLET oR.PUsaER Filed Aug. 13. was

awuewcoz EARL fl M72240? Patented Nov. 10, 1925.

:UNITED STATES PATENT OFFICE.

EARL H. WHEELER, OF WINDSORQVERMONT, .ASSIGNOR TO THE NATIONAL-1CME COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

FEED COLLET OR PUSHER.

Application filed August 13, 1923. Serial No. 657,246.

To all whom it may concern:

Be it known that I, EAnL H. WHEELER, a citizen of the United States, residing at Windsorvin the county of Windsor and State of ermont, have invented certain new and useful Im rovements in Feed Oollets or Pushers, of w ich the following is a specification.

This invention relates to'feed collets or pushers adapted for use in various types of machines, particularly metal working machines such as automatic or hand operated screw machines, bar forming machines, lathes, etc., an object of the invention being to provide an improved collet or pusher which may be cheaply and easily manufactured, and which will bemore serviceable, durable and stronger in use.

A further object of this invention is to provide a feed collet or pusher, constructed especially for attachment to the stock bar feed member or tube of a machine for gripping or feeding the stock or work and wherein the collet comprises a hollow or tubular body member having a. lengthwise extending bore therethrough, and shiftable means within said bore for gripping the workat predetermined .times and through the me:

dium of which the stock is fed by the collet.

A further object of this invention is to provide an improved feed collet or pusher comprising a tubular member having a nonexpansible portion, and expansible means supported within said non-expansible portion and operating, upon the movement of the collet to feed the stock, as a stock gripping means for the collet.

A further object of this invention is to provide an improved feed collet orvpusher comprising a hollow or tubular member provided with a tapered inner wall, and a stock gripping member supported within said collet; and having a tapered wall adapted to cooperate with the tapered wall of the tubular member for gripping the stock.

A further object of this invention is to provide an improved feed collet or pusher comprising a tubular body member having a pair of resilient ring shaped members located in the bore thereof, one of the members forming a medium for permitting the collet to grip the stock and the other forming a means for restricting the movement thereof when the collet is shifted rearwardly over the stock.

member is supported in the tapered the stock is gripped and fed upon the forward movement of the collet; Fig.2 is a slmllar view illustrating the manner in which the stock is released when the collet is shifted rearwardly over the work; Fi 8 1s a perspective View of the shiftable spring gripping member for the collet and Fig.4

1s a perspective view of the feed collet or pusher. 4 Before explaining in detail the present improvement and mode of operation thereof, I desire to have it understood. that-the invention is not limited to the details of construction and arrangement of parts which are illustrated in the accompanying drawlngs, since the invention is capable of other embodiments, .and that the phraseology which I employ is for the purpose' of description and not of limitation. I

The present feed collet or pusher does not require the provision of spring gripping fingers for feeding the stock, and in general comprises a hollow or tubular body member which is threaded at one end for at,- tachment to the stock bar-feed tube, or other feed member, of the machine. This tubular member is non-expansible, adjacent to the gripping end of the colletand the inner annular wall thereof is tapered. 'A' gripping ore and preferably comprises an annular bushing, which may be inthe form of a split ring, the inner surface of which conforms to the shape of the stock and the outer surface tapered to cooperate-with the tapered bore of the tubular. body member. This gripping memberhas a restricted sliding movement within the bore of the body member and is held from coming out when the collet is fed rearwardly over the stock'by any suitable means, such as a-removable spring. When the collet is fed forwardly 'the gripping member is heldfrom forward movement due to its friction fit overthe stock until it is wedged against the tapered walls of the pered walls of the body member and expands sufficiently to ermit the collet to slide rearwardly over t e stock.

Referring to the drawings wherein I have illustrated a present preferred form of my invention, it will be seen that the feed collet or pusher comprises an outer tubular or hollow body member 9, which may be constructed in any suitable manner. In the present instance, by way of example, this body member is formed by drilling a solid bar of stock so as to providev alengthwise extending bore 10. Adjacent to the rear end of the body member, the same is preferably turned down to providea shoulder portion 11 which is threaded for attachment to the stock feed tube or other feed member of the machine as is well-known in the art.

Adjacent to the opposite end of the body member the same is rovided with an inner tapered,bore 12 ,WlllCh extends rearwardly to a suitable point, and it will be'noted that the annular inner Walls of this portion of the collet flare or are inclined outwardly toward the. forward end of the collet. The

degree of inclination or taper of the walls 12 may of course, vary in accordance with the nature of the work to be done, but in practice Ihave found that substantially a five-degree .taper is satisfactory.

Within the tapered bore 12 of the body member a gripping member is inserted, and in the presentinstance preferably comprises an expansible and contractible ring shaped member 13. This member may be formed in any suitable manner, as for instance by drilling a piece of stock and then slotting it as at 14 to provide free juxtaposed ends 15 and 16. The gripping member 13 1s thus preferably in the form of a split ring- Which is resilient, forming an expansible and contractible stock gripping means. The inner surface 17 of thering o1" bushmg 13 is shaped to conform to the shape of the.

stock. In the present instance a round bar of stock is illustrated, and hence the bushble ring which is wedge-shaped in the direc-- tion of the length of the collet.

From the construction shown in Figs. 1 and 2 it will be observed that the ringshaped gripping member 13 will have a restricted rearward sliding movement until the cooperating tapered faces are brought into engagement. By shifting the bushing replace the entire collet as heretofore.

13 in the opposite direction the same may be readily removed from the tapered bore 12 of the body member. In use, after the bushing 13 has been inserted within the body member, a spring 19 is sprung into an annular groove 20 formed on the inner wall of the body member adjacent to the forward end thereof; This spring 19 is preferably partially coiled and may be readily inserted into the groove and removed therefrom. The spring is of sufficient gage so as to project into the tapered bore and form a stop for hunting the forward movement of the bushing 13. The inner edge 21 of the bushing or gripping member 13 is beveled or rounded so as to permit the forward end of the stock to pass readily through the bushing and the collet.

In practice, the inner diameter of the bushing 13 is preferably slightly less than the diameter of the stock, so that normally the spring bushing will have. a friction fit on the stock'and will grip it somewhat at all times. 1 In operation, It will be readily understood that when the collet is shifted forwardly in'the direction of the arrow in Fig. 1, the bushing or gripping member 13 will be wedged between the tapered walls of the bore 12-and the stock 25, which action will cause the bushing to be contracted sufficiently to firmly grip the stock and clamp the body member 9 to the stock so as to permit it to feed the stock forwardly. At the end of the feeding operation the collet is shifted rearwardly in the direction of the arrow in Fig. 2 and on account of the frictional engagement of the bushing 13 on the stock, thebody member 9 will be shifted rearwardly relatively to the bushing 13 so as to release the bushing from-the tapered walls-of the bore until the bushing engages the spring 19. The entire collet will thereupon slide rearwardly over the stock into position to be fed forwardly again.

From the foregoing construction it will be seen that an improved collet or pusher is provided having certain important advantages over collets heretofore used. For instance, when the spring bushing 13 wears out or becomes useless it is merely necessary to replace this one part without having to Furthermore, it will be observed that the bushing 13 may be readily and cheaply constructed and hence the cost of replacement thereof is slight. Moreover, the outer body member 9 may be interchan eably used for the purpose of feeding di erent sizes of stock since it is merely necessary to insert a different bushing 13 with a smaller or larger bore therethrou h in order to operate upon different sizes 0 stock. Where, during operation the bushing 13 becomes useless, 1t is not necessary as heretofore to remove the collet from the feed tube of the machine, but is is only necessary-to remove the spring 19 and the oldbushing, and insert a newione. Thus, the presentinvention accomplishes a considerablesaving in the expense of manufacture, the expense of replacement, and eliminates materially the cost of labor in manufacture and in. the operation of the machine.

It is to be understood that by describing in detail herein any particular form, structure, or arrangement, it is not intended to limit the invention beyond the terms of the several claims or the requirements of the prior art. a i

,Having thus explained the nature of my said invention anddescribed a way of constructing and using the] same, although without attempting to set forth all of the forms in which it may be made, or all of the modes of its use, I claim:

1. A feed collet comprising a hollow body having an inner lengthwise tapered bore, an annular split grippin ring located in said bore and having tie outer surface tapered to conform to the taper of said bore, said ring when shifted lengthwise within said bore expanding or contracting to conform to the size of said bore.

2. A feed collet comprising a hollow body having an inner tapered wall, an annular v wedge shaped member located within said .in said bore an tapered wall and having the juxtaposed ends spaced to permit the member to con .tract and expand, the rearportion of said tapered wall having less diameter thanthe diameter of said member when contracted, said tapered wall terminatin at its front end in an annular groove, an a spring removably located in said groove for holding said wedge member in position.

3. A feed collet comprising a hollow body having an inner lengthwise tapered bore, an annular sprin gripping member located comprisin a" split ring having the outer wall tapere to cause-said ring when shifted within said tapered bore to contract or expand, thereby to grip or release the stock.

4. A feed collet comprising a tubular body member having an inner tapered face, and an expansible and contractible wedge shaped ring located within said body member and shiftablerelatively to said tapered face to conform to the diameter thereof.

5. A feed collet comprising a tubular body member, and a pair of expansible and contractible ring shaped members located therein, one thereof being shiftable within the body member to grip the work.

Signed at Windsor, Vermont, this fourth day of August, 1923.-

i EARL H. WVHEELER. 

